Composition board and method for making the same



June 16, 1925.

R. s. KOPP COMPOSITION BOARD AND MBTHOD FOR MAKING THE SAME 2 Sheets-Sheet 1 Filed July 30, 1921 R. S. KOPP June 1.6, 1925.

COMPOSITION BQARD AND METHOD FOR MKIN G THE SAME Filed July 30. 1921 2 Sheets-Shut 2 A TTORNE Y Patented June 16,f1925. I 7

UNITED STATES,

1,542,559 PATENT OFFICE.

ROGER, S. KQPP, OF DUTLUTH, MINNESOTA, ASSIGNOR TO INTERCONTINENTAL DE- VEIIOPMENT COMPANY, A CQRPORATION 0F MARYLAND.

comr'osrnon BOARD AND METHOD For; MAKING THE SAME.

Application mea July so, 1921. SeriatNo 488,604.

To all whom it may concern:

Bejit-known that I, Room S. Kore, a citizen of the United States, and resident of Duluth, in the county of St. Louis and State of l\linnesota, have invented certain new and useful Improvements in Composition Boards and Methods for Making the Same, of which the following is a specification.

This invention relates to a composition board and to a method for making thesame,

.and more particularly to a board composed largely of wood bark, hitherto regarded in saw-mills nd in the paper making industry as a waste product. 7

The object of this inventionis the production of a fibre composition board that is strong and durable, impervious to moisture, sound-proof, non-warping, a non-conductor of heat and electricity and which will burn only with great difficult which is econominess thereof greatly increased by the addition of a binding material. The sheet thus formed is further strengthened, and its appearance and moisture resisting qualities are enhanced by pasting tough paper on both sides thereof. By thus making the sheet water proof, warping is prevented, and its strength and durability are increased.

With these and other-objects in view, I have devised the method and made the product described in, the following specification and illustrated in the accompanying drawings, of which- Figures 1 to t nclusive, when joined end to end in numerical order,.constitute a side elevation of the apparatus, said .figures be ing shown separately for convenience.

Figure 5 is a perspective View of the completed board, and I Figurefi is a cross section. of the board. Referring to the drawing, 1 represents a conveyor upon which the bark receivedfrom the tumbler or debarking plant, or othel suitable sourceris dumped. A pair of 15 to conveyor 21.

squeeze1'olls,,2 and 3, beingupper and lower respectively, are carried in frame 4, roll being mountedain bearings free to move u and down, and normally. held against roll 3 by spring 5, the compression of the latter being adjusted by nut-U. Shaker-'7, positioned under the delivery end of conveyor 1, is pivoted at 8 to frame 4, and is oscillated by an eccentric cam 9, causing it to throw the pieces of bark between rolls 2 and 3 which have scored surfaces to insure feed ing.

A large quantity of water is squeezed out of the bark in its passage between rolls 2 and 3, and drains through perforated cover ll) into trench 11, and thence into the drainage system. The crushed bark, emerging from rolls 2 and 3, falls upon conveyor Drier 13 comprises shell 14, apron 151, the latter being mounted on pulleyslti and 17 respectively, intake fans 13, exhaust duct 19, and steam (Oils 20. The bark is dropped upon one end of apron 15 from conveyor 12, and after passing through drier 13,-the bark falls from the opposite end of apron -A weighing and feeding device 22 of the type more fully disclosed in the patent to 23 by means of a spring pressed slatted,

presser frame 24, pivotally mounted at 25. Pivoted guide 26 conducts the material to the space between 11 ron 23 and frame 24. "As the stock is carried upward by the rising run of apron 23,'the surplus is removed therefrom by the action of a vibratin coinb-bar 25 mounted on the inner ends '0' arms 26, which are pivotally mounted at 27 and provided with a-counter-weight 28. Aslthe stock is carried over and down by apron 23, it is removed from the latter near upon guide 32, and thence into hopper 33,.

which is carriedflupon scale beam 34:. The

rear plate'35'of hopper 33 is hinged at 36 i 33 at predetermined intervals. Hopper 33 is balanced by weight 37, and connected to scale beam 34 and actuated by the tilting of the same, is a mechanism for stopping the travel of apron 23. Thus a predetermined quantity of stock is released. from hopper 33 at predetermined intervals, the same falling upon conveyor 38, which thus furnishes a uniform supply of stock for further operations. Pusher board 82 presses the material forward as the same is released from hopper 33,- thus forming a uniform layer. From conveyor 38 the stock falls upon conveyor 39 and is thus delivered to shredder 40, wherein it is fed between corrugated rolls4l. Shredder drum 42 rotating at a much greater peripherieal velocity than 'rolls-41, is provided vwlth steel ta er pins or The teeth which rip the bark into bre. shredded stock, is then carried by conveyor 43 to a second shredder 44, similar in '.all res ects to the foregoing, but having finer an more closely spaced shreddingteeth. From shredder 44 the stock is carried by conve or 45 to a third shredder 46, ada ted to re ilce it'to a still finer condition. on-' ve or 47 receives the stock from shredder 46.

ach of conveyors 39, 43, 45 and 47 permits the fine corky dust released by the crushing and shredding operations. to fall through, the fibre being retained. This sift-.

ing process is facilitated by the constant vibration of the conveyor. Beneath each'of the conveyors is'a grid or screen '48, through which the cork-like particles are received y scraper conveyor 49 which conducts them to pit 50; Fan 51 discharging from pit 50.

into discharge pipe 52, causes the particles to be conveyed to the boiler room, where they are introduced directly into the furnace and utilized as fuel.- Where a more positive screening action is required, con

veyors 39, 43, 45 and 47 are of the scraper type, and the stock is thereby carried across screens or grids of predetermined mesh.

From conveyor 47 the stock is received by a second weighing and feeding device 53, similar in all respects to 22 aforementioned. The sifted and finely shredded dry stock is here deposited in a smooth uniform felted ipes 56 and su ply pipes 57 connect pipes 55 with t e 58, passes between rolls 62 and 63" the latter being the glue transfer roll' andjreceiving its supply of glue from positively" driven .then passes around guide roll 66, wlth its glue covered side downward. Lower P P roll 67 is carried upon cradle rolls 68 and is positively driven. The paper 61.fr.om roll I 69, one being positively driven, and the 4 paper 70. is carried between glue transfer roll 71 and guide roll 72 with .its glue covered side up. Roll-71 contacts with'and is supplied by positively driven glue roll 73 rotati-n partially immersed in glue contained m trough 74. Guide rolls 66 and 72 are spaced apart vertically a distance about equal to that of the layer of .bark on conve or 54, and are ositioned as close to the de ivery end of t e same :as possiblex A guide75 prevents the felted layer 76 from falling after it leaves the conveyor and be-- fore reaching rolls 66 and 72.

Hydraulic press 77 compacts the composite sheet of shredded bark and paper' emerging from rolls 66 and 72. A pair of' adjustable tension rolls 78 draw'the board and a pair of circular saws 79 set at predetermined distance apart trim the edges of the sheet. A cutting machine 80, preferably of the automatic shear type and havingla knife '81, cuts the board into desired len s.

Feedingand weighing devices22 an 53, and shredders 40, 44 and 46 (excepting drums 42) together. with associated conveyors, aper feeding rolls, tension rolls 78 saws i79- and cutter 80 are connected up with chain drives and driven as a single unit through a main drive pulley supported near press 7 7 The use of a fiat press renders the process intermittent, and the above described drive system is synchronized" with press 77 by causing the latter, on its releasing movement, to effect the engagement from press 77 after the release of pressure,

of clutch of the main driving pulley and to lift knife-81 of cutter 8,0.Y'Shredding drums 42 are continuously driven, and independent drive is provided for squeeze rolls 1.2 and 3 and their associated conveyors, also 'for drier 13 and its conveyors.

In place of a power press 77 of the type shown in the drawing, heavy rolls may substituted. In such case the process may be made continuous.

The operation of the abovedescribedapparatus will-be appar nt from the descripproportion of'the liquid content is squeezed out. The'remaining moisture is removed by evaporation, and the bark is fed uniformly -tion. The bark is first crushed and a-large' through a succession of shredders, each re ducing the fibr'to a er degree of fineness, the corky content of the bark being erations. The finely Shredded bark is then u the press.

' binder.

, formed into a uniform'sheet with the long tough fibres intertwined thenimpregnate with a solution of sodium silicate, or similar binding material, which greatly strengthens the bond between the felted fibres. The layer is then fed between sheets of glued paper, preferably waterproof, such as kraft paper, and the composite layer compacted in a press, which forces the fibres into closer union and distributes the sodium silicate throughout the entire mass, also causing the; paper to adhere more firmly and giving a smooth surface. The paper being waterproof, prevents the adhesive. on its inner surface from oozing through and sticking to With regard to the corky content of the bark, the presence of the same in the finished product tends to weaken it." Consequently the sifting process should be car.-

ried sufficiently far to insure the required strength. V v

In the following claims, the term ligneousfiis intended to apply to bark fibre as well as to the fibre of Wood in its more restrittedsense. While the felting of ligneous fibre is ordinarily accomplished by flotation and capillarity, as in the paper making industry, applicant is believed to be the first to forming the shredded bark into a feltedeffect the separation and the subsequent felting of suchfibre in the absence of extraneous liuid. 1 hat I claim is:

1. The method of making a fibre board from wood bark which comprises removing water from the bark, shredding the bark, removing the c'ork-like impurities from the fibres, arranging them in a layer, applying a binder, and compressing the fibres" and 2. The method' of making, fibre board from wood bark which comprises removing water from. the bark, shredding the bark, removm fibres W ile dry,'and in alayer. I

' 3. The method of making a fibre board which comprises removing water front the arranging the fibres bark, I shredding the bark, removing the cork-like impurities from the fibres, further shredding the fibres followed again b removing the cork-like impurities, an ar- 4. 7 he method of separatmg ligneous fi'bres .andremov'ing cork-like impurities which comprises- Suecessively shredding the fibres dry.

the cork-likeimpuritiesfrom thetoseparate them, and successively removing the cork-like impurities from the fibres between the shredding operations and while A fibre board comprising a sheet of V shredded bark impregnated with binding-- material and covered on either side with a moisture resisting material.

6. A fibre board, comprising a sheet of shredded'and felted bark covered on either Sid? with a tough moisture resisting materla '7. The method of forming a fibre board shredded filling material which comprises dry shredding bark to pulverize the corklike substances without pulverizing the fibres of the-bark, and dry separating said pul verized cork-like substances from the fibres.

8. The process of treating bark to form a fibre board which comprises shredding the bark, felting the shredded material andimpregnating the same with abinder by spraying opposite sides of the felted material.

9. The method of making a bark filler for fibre board which comprises crushing and \shred'ding the bark, removing the cork-like pulverized material while dry, and forming the fibrous portion into felted sheets.

10. The method of making a bark filler fol-fibre board, which comprises drying the bark, shredding the same while dry, and

sheet.

11. The method of making a bark filler for fibre board, which comprises passing the bark through rollers to crush the same and to squeeze out a portion of the liquid con-1 tent, drying and shredding the crushed product, and forming the same into felted sheets.

12. The method of making a bark filler for fibre board, which comprises dryin thesame mto sheets.

Signed "at Duluth, in the county of St. Louisand State of Minnesota, this 18th day Of v k -RoeEn's. KoP'r. 

